perf: lazy-load xlsx/recharts, split estimate tabs, memoize nav

- xlsx dynamically imported via cached singleton in excel.ts and
  skillMatrixParser.ts (removes ~100 kB from 4 routes)
- recharts extracted into lazy-loaded SkillDistributionChart and
  PeakTimesChart components (removes ~60 kB from 3 routes)
- EstimateWorkspaceClient: 7 tab components + 2 editors loaded via
  next/dynamic (reduces /estimates/[id] from 323 kB to 138 kB)
- ImportModal lazy-loaded in ResourcesClient (deferred until open)
- NavItem memoized with React.memo, top 5 routes get prefetch=true
- Raw <img> replaced with next/image in ProjectsClient, CoverArtSection
- tRPC QueryClient: refetchOnWindowFocus/Reconnect disabled globally

Heaviest routes reduced 39-66% First Load JS:
  /analytics/skills: 383→132 kB (-66%)
  /estimates/[id]:   323→138 kB (-57%)
  /resources/[id]:   458→210 kB (-54%)
  /estimates:        310→170 kB (-45%)
  /resources:        363→222 kB (-39%)

Co-Authored-By: claude-flow <ruv@ruv.net>

apps/web/src/components/resources/ResourceDetail.tsx

@@ -2,14 +2,27 @@
 
 import { useState } from "react";
 import Link from "next/link";
+import dynamic from "next/dynamic";
 import type { AllocationLike, AllocationReadModel, AllocationWithDetails, Resource, SkillEntry } from "@planarchy/shared";
 import { trpc } from "~/lib/trpc/client.js";
 import { formatDate, formatMoney } from "~/lib/format.js";
 import { ResourceModal } from "./ResourceModal.js";
-import { SkillRadarChart } from "./SkillRadarChart.js";
-import { AiSummaryCard } from "./AiSummaryCard.js";
-import { SkillMatrixUpload } from "./SkillMatrixUpload.js";
 import { usePermissions } from "~/hooks/usePermissions.js";
+
+const SkillRadarChart = dynamic(
+  () => import("~/components/resources/SkillRadarChart.js").then((mod) => ({ default: mod.SkillRadarChart })),
+  { ssr: false, loading: () => <div className="h-64 shimmer-skeleton rounded-xl" /> },
+);
+
+const AiSummaryCard = dynamic(
+  () => import("~/components/resources/AiSummaryCard.js").then((mod) => ({ default: mod.AiSummaryCard })),
+  { ssr: false },
+);
+
+const SkillMatrixUpload = dynamic(
+  () => import("~/components/resources/SkillMatrixUpload.js").then((mod) => ({ default: mod.SkillMatrixUpload })),
+  { ssr: false },
+);
 import { InfoTooltip } from "~/components/ui/InfoTooltip.js";
 import { ProgressRing } from "~/components/ui/ProgressRing.js";
 import { FadeIn } from "~/components/ui/FadeIn.js";